TRI-COLORED BLACKBIRD. Agelaius tricolor (Audubon)

Field characters.—As for Red-winged Blackbird, but male with red shoulder patch bordered by a striking white bar, and plumage with faint iridescence. Female so similar to this sex in Red-wing that only association with male can be depended upon for identification in the field. Voice: Song of male, a scolding eskow-eskeo; call note of both sexes, a harsh throaty check.

Occurrence.—Resident locally in Lower Sonoran Zone; a nesting colony found near Tuolumne River 2 miles southwest of Lagrange. During nesting season frequents dense tule growths, foraging on open ground in vicinity. Gregarious at all seasons.

The Tri-colored Blackbird gains its name from the striking combination of color borne by the adult male. His otherwise solidly black plumage has, by way of contrast, a bright red patch on each wing, and this patch is broadly margined below by white. The female is more dully marked, wearing a streaked plumage closely resembling that of the female Red-wing. The close relationship of the Tri-color to the Red-winged Blackbirds is further evidenced by the similarity in the call notes (though not the song) and by the gregarious habits of the two species. But the Tri-color exhibits a number of differences. The song of the male is shorter and less musical, while the species as a whole maintains the flocking habit to a much more persistent degree, so that there is scarcely any relaxation of it during the breeding season. The Tri-colors nest in more compact colonies, often composed of a great many pairs, and they resort to the densest sort of tule thickets, a shelter requirement which probably explains their absence from many localities otherwise suitable. They are not known to scatter out and nest in small marshes as do the other Red-wings.

In flight the male Tri-colored Blackbird closely resembles the male Red-wing with one notable difference: the red color rarely shows, and the same is true even when the bird is perched, so that the appearance at most times is that of a white-winged blackbird.

A small but typical colony of Tri-colored Blackbirds comprising about 25 pairs was found near the Tuolumne River below Lagrange on May 7, 1919. Several pairs were seen foraging in a meadow near the river. After gathering some food material, the birds would perch in adjacent willows for a short time and then fly off, all in the same general direction, over heaps of boulders left by a gold dredger. Other pairs were arriving from time to time over the same course. By following up this line of flight we discovered the nesting area about a quarter of a mile distant in a long dredger pond which supported at its in-shore end an unusually dense stand of tules, both living and dead. This trait of the Tri-colored Blackbird to fly back and forth over a given air-course or 'highway' may thus be used in determining the location of a nesting colony, even though the latter may be a mile or more from the forage ground.

At the colony numerous pairs of adults were perched about in the small willows which grew on the shores of the pond. The males exhibited no jealousy at one another's proximity, and each accompanied his mate as the latter went in search of food for the nestlings. Zealous guarding of the nesting precincts, which is so marked a trait in the behavior of the male Red-wing, is not practiced by the Tri-color. There is not the need for each and every male to remain at the nest while the female is absent; the nests are located so very close together that there are always enough adult birds about the colony to sound an alarm should an enemy appear. It would seem as though the Tri-colored Blackbirds had attained to a more successfully communal stage of development in their domestic affairs than have the Bi-colored Red-winged Blackbirds.

The females did all the work of feeding the young; but despite their burden they carried on the work in a surprisingly deliberate manner, totally unlike the incessant activity which characterizes so many birds when rearing their broods. Each stage in the proceeding was accomplished in a leisurely manner, and the birds rested at each end of the journey to and from the forage grounds, and both before and after feeding the young. While perched near the colony, adult birds of both sexes uttered the single harsh call note at short intervals, and the males from time to time gave their short scolding song, which sounded somewhat like the words get out uttered quickly and harshly. Individual females were continually entering and leaving the tules, and as each approached her own nest the squealing calls of the young, skee, skee skeeeee, would increase in volume and then suddenly cease as their wants were satisfied. The nests were not examined closely, but it was evident that most of the eggs in the colony had hatched; still no young were seen out of the nest.